Magnet Design and Fabrication of CYCIAE-14, a 14 MeV PET Cyclotron

In line with the increasing demand for PET cyclotrons in China, the construction of a 14 MeV high intensity compact cyclotron, CYCIAE-14, has been proposed at China Institute of Atomic Energy (CIAE) in 2010 and is scheduled to be finished within two years. The fabrication is in smooth progress, with a majority of the devices ready in place for installation. As a critical part of the cyclotron, the main magnet development is of paramount importance to the successful development of the machine. At present, the main magnet design and fabrication has been accomplished. The physics design of the main magnet, which enables the realization of strong focusing by adopting a 4-sector structure with variable hill gap, will be emphatically introduced in the paper. Meanwhile, the engineering techniques applied to the fabrication will also be presented, in particular the technical challenges encountered in the process. Based on the accomplishment of two sets of main magnets, six more sets of main magnets will be fabricated.